From 1f8645fd4342fe8fb22e1cec3c15fb980ae5bebf Mon Sep 17 00:00:00 2001
From: WerWolv <werwolv98@gmail.com>
Date: Fri, 17 Mar 2023 11:43:50 +0100
Subject: [PATCH] fix: Occasional crash when multiple threads are reading data
 from a file provider

---
 lib/libimhex/include/hex/api/content_registry.hpp        | 2 +-
 lib/libimhex/include/hex/api/imhex_api.hpp               | 2 +-
 .../builtin/include/content/providers/file_provider.hpp  | 8 +++++---
 .../builtin/source/content/providers/file_provider.cpp   | 9 ++++++---
 4 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/lib/libimhex/include/hex/api/content_registry.hpp b/lib/libimhex/include/hex/api/content_registry.hpp
index 4f8449f6c..eeafaa522 100644
--- a/lib/libimhex/include/hex/api/content_registry.hpp
+++ b/lib/libimhex/include/hex/api/content_registry.hpp
@@ -385,7 +385,7 @@ namespace hex {
 
             namespace impl {
 
-                using Callback = std::function<bool(std::filesystem::path)>;
+                using Callback = std::function<bool(std::fs::path)>;
                 struct Entry {
                     std::vector<std::string> extensions;
                     Callback callback;
diff --git a/lib/libimhex/include/hex/api/imhex_api.hpp b/lib/libimhex/include/hex/api/imhex_api.hpp
index 59b91716a..30e8cd9e6 100644
--- a/lib/libimhex/include/hex/api/imhex_api.hpp
+++ b/lib/libimhex/include/hex/api/imhex_api.hpp
@@ -175,7 +175,7 @@ namespace hex {
 
                 void setBorderlessWindowMode(bool enabled);
 
-                void setCustomFontPath(const std::filesystem::path &path);
+                void setCustomFontPath(const std::fs::path &path);
                 void setFontSize(float size);
 
                 void setGPUVendor(const std::string &vendor);
diff --git a/plugins/builtin/include/content/providers/file_provider.hpp b/plugins/builtin/include/content/providers/file_provider.hpp
index 17948e067..c27c39e2e 100644
--- a/plugins/builtin/include/content/providers/file_provider.hpp
+++ b/plugins/builtin/include/content/providers/file_provider.hpp
@@ -4,9 +4,9 @@
 
 #include <wolv/io/file.hpp>
 
+#include <mutex>
 #include <string_view>
 
-
 namespace hex::plugin::builtin {
 
     class FileProvider : public hex::prv::Provider {
@@ -59,13 +59,15 @@ namespace hex::plugin::builtin {
 
     protected:
         std::fs::path m_path;
+
+        wolv::io::File m_sizeFile;
         std::map<std::thread::id, wolv::io::File> m_files;
-        size_t m_fileSize = 0;
 
         std::optional<struct stat> m_fileStats;
 
         bool m_readable = false, m_writable = false;
-        bool m_openReadOnly = true;
+
+        std::mutex m_fileAccessMutex, m_writeMutex;
     };
 
 }
\ No newline at end of file
diff --git a/plugins/builtin/source/content/providers/file_provider.cpp b/plugins/builtin/source/content/providers/file_provider.cpp
index bfb21ac66..7b89e51f7 100644
--- a/plugins/builtin/source/content/providers/file_provider.cpp
+++ b/plugins/builtin/source/content/providers/file_provider.cpp
@@ -71,6 +71,7 @@ namespace hex::plugin::builtin {
         if ((offset + size) > this->getActualSize() || buffer == nullptr || size == 0)
             return;
 
+        std::scoped_lock lock(this->m_writeMutex);
         wolv::io::File writeFile(this->m_path, wolv::io::File::Mode::Write);
         if (!writeFile.isValid())
             return;
@@ -140,7 +141,7 @@ namespace hex::plugin::builtin {
     }
 
     size_t FileProvider::getActualSize() const {
-        return this->m_fileSize;
+        return this->m_sizeFile.getSize();
     }
 
     std::string FileProvider::getName() const {
@@ -203,7 +204,7 @@ namespace hex::plugin::builtin {
         }
 
         this->m_fileStats = file.getFileInfo();
-        this->m_fileSize  = file.getSize();
+        this->m_sizeFile  = wolv::io::File(this->m_path, wolv::io::File::Mode::Read);
 
         return true;
     }
@@ -213,6 +214,8 @@ namespace hex::plugin::builtin {
     }
 
     wolv::io::File& FileProvider::getFile() {
+        std::scoped_lock lock(this->m_fileAccessMutex);
+
         if (this->m_files.size() > 5)
             this->m_files.clear();
 
@@ -229,7 +232,7 @@ namespace hex::plugin::builtin {
         std::fs::path path = std::u8string(pathString.begin(), pathString.end());
 
         if (auto projectPath = ProjectFile::getPath(); !projectPath.empty())
-            this->setPath(std::filesystem::weakly_canonical(projectPath.parent_path() / path));
+            this->setPath(std::fs::weakly_canonical(projectPath.parent_path() / path));
         else
             this->setPath(path);
     }